Condenser tube terminal



Jan. '27," 1925. P. A. BANCEL CONDENSER TUBE- TERMINAL Filed Nov. 9, 1920 6 INVEN OR Patented Jan. 27,1925.

PAUL A. BANGEL, OF NUTLEY, NEW JERSEY, ASSIGNOR TO IIl'GmSOLL-RAND (DM- 1,524,280 PATENT OFFICE,

rm, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

CONDENSER TUBE TERMINAL.

Application flledfl'ovember 9, 1920. Serial No. 422,796.

To all whom it may concem:

Be it known that I, PAUL A. BANCEL, a citizen of the United States, residing at N utley, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Condenser Tube Terminals, of which the following is a specification, accompanied by drawings.

The invention relates to the construction of condenser tubes but more especially to the terminals of consenser tubes for large surface condensers, although the tubes'and terminals may be used in any connection-in which they are found'applicable. t

In pumping water through a condensertube, there are three losses of head, the first of which is called the entrance head, amounting to approximately one-half'the velocity head if the entrance has a-square edge. Commercial condenser inlet ferrules have prac tically a square edge and cause this loss. The second loss is due to the friction along the tube which is a function of the velocity for a given tube. The third loss, is the veloeity head itself, that is, the head corresponding to the velocity of the water when it is running full bore through the tube. The head corresponding to tl'llS velocity is entirely lost ineddies when the water is discharged into the usual water box of the condenser communicating with the discharge pipe for water.

The primary objects of the present invention are to reduce the losses of head referred to especially the first and third, that is, the entrance head and the velocity head, and I am enabled toreduce these losses by means of a specially designed entrance for the tubes, and a diffuser at the discharge end of the tube in the form of a ferrule.

Another important object of the invention is to construct the inlet and the difiuser so that the tubes and terminals may be conveniently assembled and taken apart as desired.

Further objects will hereinafter appear and. to all 9f these ends the invention is shown in one of its preferred forms in the 4 accompanying drawingsin which the figure is a side view of a tions of the tube in vertical section.

Referring to the drawings, A and B represent portions of the tube sheets of a surface ndenser in which n of he tu e G condenser tube with sheets and the terminals respectively,

shown supported and provided with terminals constructed in accordance with the principles of my invention. The tube sheets A and B form the inner walls of the ,usual water boxes at the inlet and discharge sides of the condenser. In the form of the invention shown'the inlet end of the tube 0, of which there number, extends partly into an aperture D in the tube sheet A, preferably being expanded in the aperture D. The tube C is slidable in the aperture E of the tube sheet B at the opposite or discharge end and is provided with a removable diffuser ferrule P having a bore Q: of larger diameter than the tube and gradually enlarging in the direction of flow. The diffuser P is threaded partly into the tube sheet B and the tube C extends through the tube sheet and partly into the diffuser ferrule. Packing'material H is provided in the joint between the diffuser ferrule and the tube sheet and the collar R of the difluser may be screw threaded as shown in order to be'secured in the internal screw threaded socket S of the tube sheet B.

The tube sheet A is provided with an inlet F having a well-roundedentrance G substantially flush with the outer surface of the tube sheet and merging with the bore J of the tube C. In accordance with this invention I have found that the entrance G should vbe rounded or contoured in a particular manof entrance head over a square edge at the entrance, depending upon the particular design of the inlet. In constructing my improved tube terminal, particularly for the water entrance end of a surface condenser tube, it will be seen that the inner tube sheet pob A of the water box is provided with a tube aperture D cylindrical for the ma'or portion of its length, measuring from t e inner face of the tube sheet and interrupted by an inwardly extending annular shoulder, the remaining entrance portion G of the tube may be the required six. The'entrance G or its equivaaperture flaring outwardly with rounded contours term nating flush with the outer face of the tube sheet, and the condenser tube Q is expanded into the said cylindrical portion of the tube aperture with the end of the tube seated against the,said shoulder, so

that the rounded entrance portion G merges with the inner surface or bore J of the tube to permit unobstructed flow of water.

With a diffuser P of the type described the water will be discharged into the usual usual water box, of the condenser and this will help draw the water through the tube. For instance, if the discharge outlet U of the diffuser is the square root of twicethe diameter of the inlet T or smaller diameter, the area at the discharge outlet U will be twice as large,-the velocity one-half and the velocity head loss in eddies one-fourth,

- making a theoretical saving of three-fourths of" the yelocity head.

By actual demonstration I have found that the saving due to the condenser tube terminals of this invention, at the water velocities given below, are the following percentages of the friction loss through a tube of commercial length and one inch out- Side diameter having walls .049 inch thick.

' Water velocity.

Per cent of head saved over all.

As the head against which the water has to be pumped in the condenser installation .15 largely friction through the tubes, the

above percentages are approximately the savings in pumping cost at any given ve-' locity and are an indication of the increase in velocity permissible without increasing ppmping if ordinary tube terthe power for minals are used.

Another feature in regard to the use of high water velocity in large condensers, is

that suflicient water has to be passed through a tube to cause a relatively small temperature "rise in order that the final temperature to which-the water is heated may be low and the steam temperature correspond- I ingly low and the vacuum correspondingly high. This limitation, has also to be especiallyl considered in the top of a condenser at w greatest on the outside of the tubes.

My improved condenser tube terminals are not ordinarily applicable to commercial condensers heretofore on the market because in th the majority of cases the practice in large ich point the activity of the steam is condensers has been to place the tubes on close center lines with insufiicient room for the ferrules forming the subject matter of this invention. However in those types of condensers for which I have obtained and am obtaining patents having the tubes through which the great quantities of water are forced, placed on very wide centers for other reasons, the tubes can accommodate the type of ferrules under consideration.

My improved terminals become highly important in large surface condensers particularly as a means for increasing the velocity and heat transmission in certain tubes without increasing the energy expended in pumping the water through those tubes. 1 do not herein claim the arrangement and construction of tubes in a condenser. reserving this feature for a separate application, but in explaining the functions and advantages of my improved terminals it will be sufiicient to point out that in large condensers the tube bank becomes of such depth that the addition of tubes in order to increase the capacity or vacuum is likely to be prohibitive. because the added pressure drop due to the added tube. causes an increase in pressure loss through the condenser and a corresponding reduction in temperature down through the tube nest.

Stated in anotherway, it is highly desirable and important in adding tubes to the toplof a condenser in order to increase its vacuum, that the number of tubes added to do a certain amount of work be a minimum, thus allowing a maximum space for the passage of steam with the least loss of pressure. The importance of this feature is magnified in large condensers in which the proper design of the foundations for the power unit as for instance a turbine, im-

poses limitations upon the width of the tube bank. In the extreme case. it would be desirable to secure the additional capacity by a single tube working at an enormous rate of condensation. I

, ThlS condition, however, may be approached by providing my improved terminals and the use of a relatively small number of tubes each working at a very high rate of condensation secured by high water velocity. It is also true that this reduction in the amount of surface is desirable for the reasons given. entirely independent of the saving secured by the use of asmaller investment in brass, a smaller replacement investment and a greater cleanliness mamtenance I claim:

A tube terminal for the watertfentrance end of a surface condenser tube, consisting of an inner tube sheet of a water box proe major portion 0 vided with a tube aperture cylindrical for its length measuring from the "inner face of the tube sheet and interrupted by an inwardly extending annular shoulder, the remaining entrance portion of the tube aperture flaring outwardly with rounded contours terminating flush 5 with the outer face of the tube sheet, and a condenser tube expanded into the said cylindrical'portion of the tube aperture with the end of the tube seated against said shoulder, whereby the rounded entrance portion of the aperture merges with the inner sur- 1 face of the tube to permit unobstructed flow of liquid.

In testimony whereof I have signed this specification.

PAUL, A. BANCEL. 

